1. Field of the Invention
The present invention relates to a post and core assembly for dental implants. More particularly, the post and core assembly is constructed such that the post and core may be welded together, by a method such as laser welding, at an appropriate angle to compensate for any misalignment of the anchor which receives the post and core assembly.
2. Description of the Prior Art
When a dental prosthesis is to be attached to a patient's jaw it must be properly aligned with the other teeth or prostheses so as to be parallel thereto. A problem arises when an anchor receiving the post and core is inserted into the jaw at an angle not suitable for proper alignment. This may occur because bone tissue capable of securely supporting the anchor is not advantageously situated for appropriate placement of the anchor, or because it is simply too difficult to install properly in the available space.
An example of the former approach incorporating a rotatably adjustable post and core assembly is shown in U.S. Pat. No. 5,316,477, issued to Luis O. Calderon on May 31, 1994. Calderon's post and core must have an anchor having a circular hole for receiving the core. By contrast, the present invention has a conventional hexagonal core which cooperates with a conventional anchor having a hexagonal hole. Also, the degree of tilt, or deviation from the axis of the post and core, is adjustable in the present invention.
An example of the latter compensating approach incorporating a rotatably adjustable post and core assembly employing reference marks is shown in U.S. Pat. No. 5,350,301, issued to Vincent De Buck on Sep. 27, 1994. The post and core are provided as two separate, subsequently united structures in this invention. By contrast with the present invention, no part is deflectable into the desired position in the De Buck invention. Rather, in the De Buck device, an assembly incorporating a desired angle must be built up from individual components.
An even more complicated built up post and core assembly is described in U.S. Pat. No. 5,350,302, issued to Gerald M. Martin on Sep. 27, 1994. Some of the components of the post and core assembly have screw bores and mounting cavities which are misaligned, so that the component can be screwed to a supporting component. A subsequently mounted member continues at an angle to the supporting component. The various components allow for progressive adjustment to suit conditions as successive components are assembled and oriented at new angles to their predecessors.
U.S. Pat. No. 5,073,110, issued to Noram K. Barbone on Dec. 17, 1991, illustrates a post and core assembly wherein the post comprises the ball of a ball and socket joint. The anchor provides the socket. Unlike the present invention, which employs a conventional hexagonal core compatible with a conventional anchor having a hexagonal hole, the anchor of the Barbone device is configured to receive a ball. The Barbone anchor must be designed from the outset to cooperate with its associated post and core. Unlike the present invention, Barbone's apparatus is not deflectable.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.